Massachusetts maintains restrictive knife laws focused on specific types rather than universal blade lengths, shaped by Mass. Gen. Laws ch. 269 § 10(b). A 2024 Supreme Judicial Court ruling in Commonwealth v. Canjura legalized automatic knives (switchblades) under 3 inches for adults 21+, easing prior bans, though other restrictions persist.
Legal Knife Types
Pocket knives, folding knives, and multi-tools without prohibited features (e.g., no double-edged blades, stilettos, dirks, daggers, or ballistic knives) are generally permissible statewide. Fixed blades are allowed openly if not offensive designs, but intent governs legality—tools for utility differ from weapons.
Automatic knives now qualify if blades stay under 3 inches and carried by eligible adults; no length cap applies to non-automatics absent local rules.
Carry Restrictions
State law prohibits carrying listed “dangerous weapons” on one’s person or in vehicles, without distinguishing open vs. concealed. Boston caps blades at 2.5 inches; Cambridge, Worcester, and Malden impose similar municipal limits (e.g., no blades over 2.5 inches for minors under 18 in some areas).
No statewide preemption means cities enforce stricter ordinances—carry conservatively in urban zones.
Age and Intent Rules
Adults 18+ handle most legal knives; 21+ for autos post-Canjura. Minors face purchase/use bans in places like Boston (blades >2 inches). Criminal intent converts legal carry into assault with a dangerous weapon charges.
Schools, courthouses, and secure buildings ban all knives universally.
Prohibited Features
Banned statewide: double-edged blades, propelled/detachable blades, stilettos, and offensive designs per § 10(b). Violations are misdemeanors or felonies based on use, with fines up to $1,000 and jail time.
| Knife Type | Blade Limit | Legal for Adults? |
|---|---|---|
| Folding/Pocket | None | Yes |
| Automatic | <3 inches | 21+ Yes |
| Fixed Blade | None (type-based) | Yes, open/utility |
| Stiletto/Dagger | Any | No |
Enforcement Tips
Holster visibly as a tool; avoid brandishing. Courts assess context—work/hiking justifications succeed. Verify local codes via city sites; 2026 laws unchanged post-Canjura.
SOURCES :
- https://www.tektoknives.com/blogs/news/massachusetts-knife-law-update-switchblades-now-legal
- https://knifeinformer.com/state-knife-laws/massachusetts/
